burmester



Oct. 2, 1928. 11,686,070

L. BURMESTER AIR HEALING FURNACE Filed Feb. 21, 1928 2 Sheets-Sheet 1 ATTORNEY.

Oct. 2, 1928.

L. BURMESTER #IRHEALING FURNACE 2 Sheets-Sheet 2 Filed Feb. 21, 1928 [NVEN TOR.

Zia/W Patented Get. 2, 1928..

rates AIR-HEATING FURNACE.

Application filed. February 21, 1928. Serial No. 255,884.

The invention relates to air heating fur- 'naces, particularly of the type shown in PatcntNo. 1,651,668 dated Dec. 6. 1927, and issued to me and A. Munroe jointly, and has for its object to provide beneath the tube holding drum a chambered casing forming a combustion chamber in which is disposed a heating element, and tubes leading upwardly from said casing and discharging into the lower side of the tube casing, whereby the heated air will circulate between the tubes in the tube casing, for heating the air circulating through the tubes.

A further object is to form the lower corner of the tube casing flat and horizontally disposed whereby a relatively compact structure is formed and suiiicient space provided for the combustion casing without materi ally adding to the height of the furnace as a whole.

A further object is to provide bars at opposite sides of the combustion chamber casing for supporting said casing and termi nating at their upper end in diverging por tions secured to the upwardly diverging sides of the tube casing.

A. further object is to provide a main casing housing the tube and combustion chamber casing and provided with discharge openings and with air intake openings through which fresh air passes, is heated in its passage through the tubes and is discharged.

l Vith the above and other objects in view the invention resides in the combination and arrangement of parts as hereinafter setforth, shown in the drawings, described and claimed, it being understood that changes in the precise embodiment of the invention may be made within the scope of what is claimed without departing from the spirit of the invention.

In the drawing:

Figure 1 is a front elevation of the furnace, showing parts and tube casings broken away.

Figure 2 is a vertical longitudinal sectional View through the furnace-main casing, shown the parts in side elevation.

Figure 3 is. a perspective view of the combustion chamber casing and tube casing.

Referring to the drawings, the numeral 1 designates the main casing and 2 fresh air pipes leading into the main casing, and through which fresh air pipes air passes into the casing 1, is heated by the device and are discharged into the tube casing 9 hereinafter set forth, then is discharged through the discharge openings 3 to the atmosphere or into pipes which may lead to any suitable point of discharge, for instance the rooms of a house. Disposed within the main casing 1 adjacent its lower end is a combustion chamber casing 4, in which may be disposed. any kind of heating element, however for purposes of illustration a gas burner 5 is shown. In some cases it' may be desirable to use an oil burner, an electric heating unit or some other type of heating unit, and it is to be understood that applicant does not limit himself in this regard. ii /ecured to opposite sides of the combustion chamber 4 are vertically disposed bars 6, which bars have their upper ends provided with upwardly diverging arms 7, which arms are secured to the opposite upwardly diverging sides 8 of the tube casing 9, whereby it will be seen that the casing 9 is supported above the casing l and forms a single unit therewith, which can be readily placed within the main casing 1. In devices of this character heretofore used, the heating element has been placed in the lower corner of the tube drum 9, as shown in my patent above referred to, however this has disadvantages as the tubes are too nearly in direct contact with the flames, and require the use of too heavy material,and to overcome this diliiculty the present device is primarily designed, that is to take the heating element out of the tube casing, and to accomplish this result without materially adding to the height of the device, the lower corner of the tube casing 9 is cut away, thereby forming a horizontally disposed fiat surface or wall 10, and the heat and products of combustion pass upwardly through the pipes 11, which connect the wall 10 and the casing a,

where they circulate between the crossed tubes 12, thereby heating said tubes and heating the air which passes through the tubes from the chamber of the casing 1, and consequently the fresh air which has been taken in through the pipes 2 passes upwardly, and thence through the discharge openings 3. After the heated air has per formed its function and cooled, it naturally falls and is discharged through the pipe 13 to, a flue or other point of discharge.

The combustion chamber 4 at its rear end is provided with a discharge pipe 14, which discharges into the tube casing 9, and is preferably provided with a controllable closure member 15, which will allow passage of obnoxious or poisonous gases to the discharge pipe 13 when certain fuels are used, however the use of this pipe is optional according to the kind of fuel used.

From the above it will be seen that an air heating furnace is provided which is simple in construction, has its heating unit in a separate casing from the tube casing, and one wherein there is no danger of the products of combustion mixing with the heated air. It will also be seen that the device will heat a continuous flow of fresh air, and if desired would heat a recirculating flow of fresh air.

The invention having been set forth what is claimed as new and useful is:

1'. An air heating furnace comprising a main casing, a tube carrying casing within the main casing, said tube carrying casing having diagonal corners in a vertical plane, a combustion chamber casing below the tube carrying casing, discharge pipes connecting the combustion chamber casing and the tube carrying casing, a discharge pipe connecting the rear side of the combustion chamber casing and the tube carrying casing and means for closing said last named pipe.

2. An air heating furnace comprising a main casing having intake and discharge openings, a tube carrying casing within the main casingand having tubes extending en tirely through the same, said tube carrying casing being rectangularly shaped and having diagonal corners in a vertical plane, the lower corner being cut away thereby'forming a flat wall, a combustion chamber casing below the tube casing and pipe connections between the combustion chamber casing and the tube carrying casing whereby heated air will pass into the tube carrying casing.

3. An air heating furnace comprising a main casing having air intake anddischarge ports, a tube carrying casing Within the main easing, tubes in said tube carrying casing and extending entirely through the same in crossed relation, a combustion chamber casing beneath the tube carrying casing, a heating element in said last named casing; and supporting barssecured to opposite sides of the combustion chamber casing, said bars In ing their upper ends connected to the tube carrying casing in diverging relation.

In testimony whereof I hereunto affix my signature.

LOUIS BURMESTER; 

